SAITO, T., HAYASAKA, S., YABATA, K., OMURA, K., MIzuwo, K. and TADA, K. Atypical Gyrate Atrophy of the Choroid and Retina and Iminoglycinuria. Tohoku J. exp. Med., 1981, 135 (3), 331-332 A 44-year-old woman with atypical gyrate atrophy and iminoglycinuria was described. The serum ornithine level and ornithine-ketoacid transaminase (OKT) activity were both normal. Urinary excretion of proline, hydroxyproline and glycine was markedly increased. This finding, together with the existence of gyrate atrophy with hyperornithinemia due to OKT deficiency, suggests that proline deficiency in the chorioretinal tissues may concern the development of gyrate atrophy.-chorioretinal atrophy; hyperornithinemia; iminoglycinuria; proline

Gyrate atrophy is a rare, inherited disease of chorioretinal atrophy. The plasma level of ornithine was found to be increased in affected patients (Simell and Takki 1973), and OKT in cultured skin fibroblasts was deficient in these patients. However, the mechanism of the ocular disturbance is still obscure because other patients with a similar degree of hyperornithinemia have no ocular problems (Gatfield et al. 1975) and there are cases of gyrate atrophy without hyperornithinemia(Jaeger et al. 1979). Recently we had a peculiar case which showed fundus changes similar to gyrate atrophy but lacked hyperornithinemia and in which urinary concentrations of iminoacids and glycine were markedly increased.